package com.qingcheng.service.impl;

import com.qingcheng.pojo.user.User;

import java.util.HashMap;
import java.util.Map;

public class Demo {
    public static void main(String[] args) {
        Map<String, User> map= new HashMap();
        User user=new User();
        user.setUsername("aaa");
        map.put("1",user);
        System.out.println(map.get("1"));
        User user1 = map.get("1");
        user1.setUsername("bbb");
        System.out.println(map.get("1"));
    }
}
